Hydroxypropyl methylcellulose (HPMC) yog cov khoom siv polymer uas muaj ntau yam siv hauv ntau yam lag luam, suav nrog kev tsim kho, tshuaj, zaub mov, thiab tshuaj pleev ib ce. Hauv kev tsim kho, HPMC plays lub luag haujlwm tseem ceeb hauv cov khoom siv cement-based, tshwj xeeb hauv kev txhim kho kev sib raug zoo.
1.Introduction to HPMC:
HPMC yog ib tug semi-synthetic, dej-soluble polymer muab tau los ntawm cellulose. Nws yog feem ntau siv los ua cov thickener, binder, zaj duab xis-yav dhau los, thiab dej tuav tus neeg sawv cev. Hauv kev tsim kho, HPMC feem ntau yog siv los hloov cov khoom ntawm cov khoom siv cement. Cov kev hloov kho no suav nrog kev txhim kho kev ua haujlwm, kev tuav dej, kev sib txuas, thiab kev ua haujlwm tag nrho.
2. Cov yam ntxwv cuam tshuam rau Bonding Strength:
Ua ntej sib tham txog yuav ua li cas HPMC txhim kho kev sib raug zoo, nws yog ib qho tseem ceeb kom nkag siab txog yam uas cuam tshuam rau kev sib raug zoo hauv cov ntaub ntawv cementitious:
Kev Npaj Nto: Cov xwm txheej ntawm lub substrate nto cuam tshuam rau kev sib khi lub zog. Ib tug huv, ntxhib nto muab zoo adhesion piv rau ib tug du los yog kab mob.
Adhesive Properties: Cov nplaum siv thiab nws cov kev sib raug zoo nrog cov khoom siv substrate ua lub luag haujlwm tseem ceeb hauv kev txiav txim siab kev sib raug zoo.
Mechanical Interlocking: Microscopic irregularities ntawm lub substrate nto tsim mechanical interlocking nrog cov nplaum, txhim khu kev ruaj ntseg.
Chemical Interaction: Cov tshuaj lom neeg sib cuam tshuam ntawm cov nplaum thiab cov substrate, xws li cov tshuaj tiv thaiv dej hauv cov khoom siv cement, ua rau muaj zog sib txuas.
3.Mechanisms ntawm HPMC hauv Kev Txhim Kho Bonding Strength:
HPMC txhim kho kev sib raug zoo los ntawm ntau lub tshuab, suav nrog:
Kev tuav dej: HPMC muaj peev xwm tuav tau dej siab, uas tiv thaiv kom qhuav sai ntawm cov nplaum thiab substrate. Kev muaj dej txaus txaus txhawb nqa cov tshuaj tiv thaiv hydration, ua kom muaj kev txhim kho kom zoo ntawm daim ntawv cog lus.
Ua kom muaj peev xwm ua tau zoo: HPMC txhim kho kev ua haujlwm ntawm cov cementitious sib tov, tso cai rau kev tso chaw zoo dua thiab kev sib cog lus. Compaction kom zoo txo qhov voids thiab ua kom muaj kev sib raug zoo ntawm cov nplaum thiab substrate, txhim kho kev sib raug zoo.
Txhim kho Cohesion: HPMC ua cov thickener thiab binder, txhim kho kev sib koom ua ke ntawm cov ntaub ntawv cementitious. Txhim kho kev sib koom ua ke txo qis qhov tshwm sim ntawm kev sib cais thiab los ntshav, ua rau muaj kev sib txuam ntau dua thiab muaj zog sib txuas.
Txo Shrinkage: HPMC txo qhov shrinkage ntawm cement-based cov ntaub ntawv thaum kho. Qhov tsawg kawg nkaus shrinkage tiv thaiv kev txhim kho ntawm cov kab nrib pleb ntawm daim ntawv cog lus interface, uas tuaj yeem cuam tshuam kev sib raug zoo.
Enhanced Adhesion: HPMC txhawb nqa adhesion los ntawm kev tsim cov yeeb yaj kiab ruaj khov ntawm qhov chaw substrate. Cov yeeb yaj kiab no muab qhov sib txuas sib txuas rau kev sib txuas thiab txhim kho lub peev xwm ntub dej ntawm cov nplaum, ua kom zoo dua adhesion.
Lub Sijhawm Tswjhwm: HPMC tuaj yeem hloov kho lub sijhawm teem sijhawm ntawm cov ntaub ntawv cementitious, tso cai rau lub sijhawm txaus rau kev sib raug zoo tsim nyog. Kev tswj qhov chaw tiv thaiv kom tsis txhob ntxov ntxov ntawm cov nplaum, ua kom pom kev txhim kho kev sib raug zoo.
4. Daim ntawv thov thiab kev txiav txim siab:
Hauv kev tsim kho, HPMC pom muaj kev siv dav hauv ntau yam kev siv uas kev sib koom ua ke yog qhov tseem ceeb:
Pobzeb Adhesives: HPMC feem ntau muab tso rau hauv pobzeb nplaum los txhim kho kev sib raug zoo thiab kev ua haujlwm. Nws ua kom ntseeg tau qhov adhesion ntawm cov vuas rau substrates, txhim khu kev ruaj khov thiab ntev.
mortars thiab Renders: HPMC tau ntxiv rau mortar thiab muab cov qauv tsim los txhim kho kev sib raug zoo thiab kev sib koom ua ke. Nws txhim kho kev ua haujlwm ntawm cov ntaub ntawv no hauv kev siv xws li plastering, rendering, thiab masonry.
Self-Leveling Compounds: HPMC pab txhawb rau kev ua tau zoo ntawm tus kheej-leveling compounds los ntawm kev txhim kho cov khoom ntws thiab kev sib koom ua ke. Nws ua kom muaj kev tiv thaiv ib puag ncig thiab adhesion rau lub substrate, ua rau cov npoo du thiab qib.
Grouts: HPMC yog siv rau hauv grout formulations los txhim kho kev sib raug zoo zog thiab tiv thaiv shrinkage-txog teeb meem. Nws txhim kho cov dej ntws thiab kev ua haujlwm ntawm grouts, ua kom yooj yim sau cov pob qij txha thiab qhov khoob.
Hydroxypropyl methylcellulose (HPMC) ua lub luag haujlwm tseem ceeb hauv kev txhim kho kev sib raug zoo hauv cov ntaub ntawv cementitious los ntawm kev txhim kho cov dej tuav, kev ua haujlwm, kev sib koom ua ke, adhesion, thiab tswj kev shrinkage thiab teem sij hawm. Nws cov khoom siv ntau yam ua rau nws muaj txiaj ntsig zoo hauv ntau daim ntawv thov kev tsim kho, ua kom ruaj khov thiab txhim khu kev qha kev sib txuas ntawm substrates thiab cov nplaum. Nkag siab txog cov txheej txheem uas HPMC txhim kho kev sib raug zoo yog qhov tseem ceeb rau kev txhim kho nws txoj kev siv thiab ua tiav cov txiaj ntsig kev xav tau hauv kev tsim kho.
Post lub sij hawm: May-07-2024